Correct.
Works just fine with older units, just not the new postion/vehicle size pieces (which frankly…well, I’ll save that for my review). Otherwise, it pairs on the existing ANT+ protocol just fine (and for example, used it with the Wahoo ROAM without any issues, minus not having the vehicle size/position pieces).
These are the vevhicle size/position pieces, where vehicles are categorized into three sizes (car-van/bus-truck-big/moto-bike), and then onto relative lane positions. These were both taken on two-lane roads (surprisingly hard to find around my area).
Below, city bus just about to pass me.
To behonest, it’s near impossible to see the difference between car and big bus on the screen at a glance. Though, the bike/moto one is easier, but I find it mis-categorizes a bunch. Seen below,
